drm/amd/display: Expand dc to use 16.16 bit backlight

[Why] We want to increase precision for backlight setting.
But DC interface takes 8 bit backlight level value only.

[How] DMCU already takes 16 bit backlight level.
Expand the DC interface to take 16.16 bit value.
Max 32 bit backlight value (0xFFFF) will represent
max backlight (100%)

Signed-off-by: Anthony Koo <Anthony.Koo@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 19 insertions, 15 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index f4936f7c5545..643407d18cce 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -2141,14 +2141,16 @@ int dc_link_get_backlight_level(const struct dc_link *link)
 {
 	struct abm *abm = link->ctx->dc->res_pool->abm;
 
-	if (abm == NULL || abm->funcs->get_current_backlight_8_bit == NULL)
+	if (abm == NULL || abm->funcs->get_current_backlight == NULL)
 		return DC_ERROR_UNEXPECTED;
 
-	return (int) abm->funcs->get_current_backlight_8_bit(abm);
+	return (int) abm->funcs->get_current_backlight(abm);
 }
 
-bool dc_link_set_backlight_level(const struct dc_link *link, uint32_t level,
-		uint32_t frame_ramp, const struct dc_stream_state *stream)
+bool dc_link_set_backlight_level(const struct dc_link *link,
+		uint32_t backlight_pwm_u16_16,
+		uint32_t frame_ramp,
+		const struct dc_stream_state *stream)
 {
 	struct dc  *core_dc = link->ctx->dc;
 	struct abm *abm = core_dc->res_pool->abm;
@@ -2160,19 +2162,17 @@ bool dc_link_set_backlight_level(const struct dc_link *link, uint32_t level,
 
 	if ((dmcu == NULL) ||
 		(abm == NULL) ||
-		(abm->funcs->set_backlight_level == NULL))
+		(abm->funcs->set_backlight_level_pwm == NULL))
 		return false;
 
-	if (stream) {
-		if (stream->bl_pwm_level == EDP_BACKLIGHT_RAMP_DISABLE_LEVEL)
-			frame_ramp = 0;
-
-		((struct dc_stream_state *)stream)->bl_pwm_level = level;
-	}
+	if (stream)
+		((struct dc_stream_state *)stream)->bl_pwm_level =
+				backlight_pwm_u16_16;
 
 	use_smooth_brightness = dmcu->funcs->is_dmcu_initialized(dmcu);
 
-	DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n", level, level);
+	DC_LOG_BACKLIGHT("New Backlight level: %d (0x%X)\n",
+			backlight_pwm_u16_16, backlight_pwm_u16_16);
 
 	if (dc_is_embedded_signal(link->connector_signal)) {
 		if (stream != NULL) {
@@ -2189,9 +2189,9 @@ bool dc_link_set_backlight_level(const struct dc_link *link, uint32_t level,
 						1;
 			}
 		}
-		abm->funcs->set_backlight_level(
+		abm->funcs->set_backlight_level_pwm(
 				abm,
-				level,
+				backlight_pwm_u16_16,
 				frame_ramp,
 				controller_id,
 				use_smooth_brightness);
@@ -2205,7 +2205,7 @@ bool dc_link_set_abm_disable(const struct dc_link *link)
 	struct dc  *core_dc = link->ctx->dc;
 	struct abm *abm = core_dc->res_pool->abm;
 
-	if ((abm == NULL) || (abm->funcs->set_backlight_level == NULL))
+	if ((abm == NULL) || (abm->funcs->set_backlight_level_pwm == NULL))
 		return false;
 
 	abm->funcs->set_abm_immediate_disable(abm);
@@ -2594,6 +2594,10 @@ void core_link_enable_stream(
 		core_dc->hwss.unblank_stream(pipe_ctx,
 			&pipe_ctx->stream->sink->link->cur_link_settings);
 
+		dc_link_set_backlight_level(pipe_ctx->stream->sink->link,
+				pipe_ctx->stream->bl_pwm_level,
+				0,
+				pipe_ctx->stream);
 	}
 
 }